What hazardous substance is found in some electrical components?

Polychlorinated biphenyls (PCBs) are indeed a hazardous substance that has historically been found in some electrical components, particularly in older transformers and capacitors. PCBs were widely used for their insulating and cooling properties in electrical equipment due to their chemical stability and non-flammable nature. However, it became clear that PCBs pose significant health risks, including potential carcinogenic effects, and they also harm the environment. This led to regulations banning their use and requiring proper disposal of products containing PCBs.

While lead, asbestos, and chlorine might also be associated with toxic substances in other contexts, they are not typically found directly in electrical components as PCBs are. Lead may be present in some soldering materials and circuit boards, while asbestos is primarily recognized for its use in insulation and fireproofing materials rather than electrical components, and chlorine is more related to chemical processes rather than a direct component in electrical systems. Hence, the recognition of PCBs as a hazardous substance specific to electrical equipment makes this answer particularly relevant and accurate in addressing the question about hazardous substances in such contexts.